These studies examine the physiological, behavioral and subjective effects of sedative drugs in non-drug abusing volunteers. They explore the basis of individual differences in preferences, investigate pharmacological factors that affect drug responses, and explore the interaction between drug-taking environment and responses to psychoactive drugs. Normal social drinkers will participate in 7-session experiments testing diazepam, pentobarbital, buspirone, oxazepam, ethanol and placebo.